Have done these in groups and raids there is the following to consider:
You want a 50 lvl rift. This give the high end loot, such as Minor Catalyst, eternal planar dust and so forth.
Major rifts give more loot than minors, but are very hard to find.
A raid that is at least 1/2 full will close a minor rift in about 3 minutes. a major in about 6.
Everyone has to stay togather and move as quickly as possible. this is because there is alot of competition for rifts, and you will have others opening or closing them if you have to wait alot.
Everyone who participates in a crafting rift gets the loot, not just the opening group/raid.
In Stillmore, it is usually better to wait for a rift in the western and southwestern area instead of running to the rifts in the north or south due to distance and difficulty to reach. Sometimes this is not true if multiples spawn in those areas.
Crafting lures will not work on raid rifts.